The grace of God is the ultimate solution in our quest for self improvement. Many experts get wordy about it, but to put it simply: we can’t actually become perfect or optimal on our own. However, God is willing to fix whatever is wrong with us through grace. Then, he wants to work through us to fix the corruption and sickness in the world.

This video by the channel Desiring God gives a more detailed explanation using examples in the Bible, especially the letters of Paul.